The term "11 septem" functions as a proper noun. It operates as a single nominal unit to name a specific calendar date. In this construction, "11" is a cardinal number specifying the day, while "septem" is the Latin word for "seven," serving as the etymological root for the month of September.
Grammatically, the number "11" acts as a numerical determiner or adjective modifying the noun "Septem." Although "Septem" is not the complete, conventional English name of the month, its use in this context is to signify "September." The entire phrase, therefore, constitutes a compound proper noun. This is analogous to other date-based proper nouns like "July Fourth." Its classification as a proper noun distinguishes it from a descriptive phrase; it does not describe a date but rather names it as a unique entity, often one with specific historical or cultural significance.
Identifying this term as a proper noun is critical for syntactical analysis. As a proper noun, it can serve as the subject of a sentence (e.g., "11 septem altered global politics."), a direct object, or the object of a preposition. This grammatical function allows the term to be treated as the name of a specific, singular event, enabling a focused and coherent discussion within an article, rather than being treated as a simple combination of a number and a separate word.
